The ChromoTek Spot-Trap® is an affinity resin for immunoprecipitation of Spot-tagged proteins.
It consists of an anti-Spot-Tag Nanobody/ VHH, which is conjugated to beads.

Immunoprecipitation (IP)/ Co-IP
IP/ Co-IP for mass spec (MS) analysis
For protein purification use Spot-Cap

For detailed decision guidance between Spot-Trap and Spot-Cap, click here.

Spot-Tag is an inert 12 amino acid peptide tag with the sequence PDRVRAVSHWSS and can be cloned to N- and C-terminus.
Please find more information about the Spot-Tag here.

Spot-Trap Agarose
Spot-Trap Magnetic Agarose
Spot VHH, recombinant binding protein
iST Spot-Trap Kit for IP plus sample preparation for MS

anti-Spot VHH, Spot binding protein, Spot Nanobody, or anti-Spot single domain antibody fragment (sdAb)

Benefit from Spot-Trap for Immunoprecipitation (IP)

  • Reduced background
  • High binding affinity, low dissociation constant KD of 6 nM for Spot fusion proteins
  • Harsh washing conditions
  • High reproducibility
  • Short incubation time of 30-60 minutes
  • Extraordinary low background compared to other affinity resins

Format/matrices & properties

We offer the Spot VHH coupled to agarose beads and magnetic agarose beads,  or uncoupled as purified protein.

  Spot-Trap agarose Spot-Trap magnetic agarose
matrix agarose magnetic agarose
color white black
particle size 90 µm 40 µm
binding capacity 1.4 µg/µL 1.4 µg/µ
magnetic no yes
may be centrifuged up to 2,500 x g 800 x g


Regeneration of Spot-Trap beads is possible. It is recommended, however, to re-use beads for the repeated purification of the same protein only to avoid cross-contamination.


Spot-Trap binds to the sequence motif PDRVRAVSHWSS.

Spot-Trap is a very low background affinity reagent. See benchmark of Spot-Trap Agarose and Magnetic Agarose with other suppliers’ capture tools. Immunoprecipitations were conducted from HEK293T cell lysates without Spot-Tag present and normalized for equal binding capacity. The IPs were done according to respective manufacturers’ protocols. It is apparent that Spot-Trap does not only lack heavy and light chain antibody contaminations but also unspecific binding. This makes Spot-Trap a superior affinity capture tool for single band purification of Spot-tagged proteins.

About Spot

ChromoTek’s proprietary and novel Spot-System is the first peptide-tag specific Nanobody for universal capture & detection applications. It comprises Spot-Tag®, an inert 12 amino acid peptide-tag (PDRVRAVSHWSS), which has been affinity optimized, and the universal, rugged Spot-Nanobody that specifically binds to Spot-tagged proteins with high affinity.
Spot-Tag peptide is derived from the protein beta-catenin: its sequence has been optimized for higher affinity binding to the Spot-Tag Nanobody. For further information see here.


Spot-Label samples available

Request a free sample here and test the all-rounder Spot in you experiment.

Download Whitepaper
Order Free Test-Sample
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Only for research applications, not for diagnostic or therapeutic use!